1. Field of the Invention
This invention relates to a method for controlling and allocating an airtime provided to Wi-Fi clients, and more particularly, to a method for providing an equal distribution of the airtime to the Wi-Fi clients connected to an access point regardless of client devices' channel speed and a connection quality metric.
2. Description of the Related Art
Use of Wi-Fi access point (APs) by several clients often creates a problem of slow Internet (or network) speed experienced by some clients, while the output of the AP is sufficiently high for providing acceptable speed for all active clients. The Wi-Fi access points connected to a number of clients share their available bandwidth based on the individual client device's channel speed and a connection quality metric. The client's channel speed is based on the channel bandwidth (BW) and on the modulation type. The Client Connection Quality (CCQ) is a percentage value, which determines the effective use of the bandwidth with respect to maximum available bandwidth.
A weak client connection (e.g., due to an interference, weak signal, content type in transit, distance from the AP, Wi-Fi device sensitivity, IEEE 802.11 revisions, etc.) can take up a large portion of the airtime at the AP, and, consequently, the AP allocates a shorter airtime to other connected active clients, reducing their send and receive throughput and airtime, effectively slowing down the Wi-Fi network. In this case, although the potential throughput of the AP remaining the same, the perception and the actual performance at the client level decreases dramatically.
An example of the above situation is illustrated in FIG. 1. Client 1 is connected to the AP, but has a low channel speed (CS) due to its data rate and modulation type and a low CCQ value for its connection quality to the AP. In this case, this connection takes a large portion of available airtime to the Access Point, since it holds the transmission opportunity. Client 2 has a higher channel speed capability, due to its data rate and modulation type, as well as much higher CCQ value indicating its higher connection quality. However, Client 2 is slowed down because it receives a lower amount of airtime due to Client's 1 continued transmission session. Client 3, having similar connectivity attributes to Client 2, will be slowed down further, since it will be assigned even less airtime.
As a result, one client (e.g., Client 1) connection transmitting with a poor connection quality will slow down the entire network connection to the AP for the rest of the active clients (e.g., Client 2 and Client 3). This can gradually bring the entire network to halt. Depending on which client grabs the connection first, the network might randomly provide some relief, but the performance of the network will still suffer due to one or many clients having poor connection quality.
Accordingly, it is desired to have a method, which implements an algorithm for monitoring connections for all active clients and automatically recalculating the channel speed and the airtime for each active connection and shaping Wi-Fi channel's bandwidth to provide equal airtime to each active connection. This optimization process needs to be activated each time a new client connects to the AP or whenever a change in client's channel speed and/or CCQ parameters occurs.